The proposed Phase II SBIR project will extend, refine, and test CAS-2, a tool for building and running clinical advice programs, which was developed as a prototype in Phase I of this project CAS-2 currently allows a clinical knowledge base (KB) to be 1) built, 2) edited, and 3) run for test purposes, all using the graphical user interface (GUI) of a Macintosh computer running the 4th Dimension (4D) database package. The proposed project will refine, extend, and test CAS-2 in a number of ways. 1) CAS-2 will be used to build several different types of KBs to help determine what types of data and logic are required to deal with a range of clinical KBs. 2) The data and logic allowed in CAS-2 will be extended. 3) CAS-2 will be extended to allow images and graphical figures. 4) CAS-2 will be extended to allow the KB to be run operationally using the native GUI of a variety of machines (including Macintoshes and PCs with MS Windows) using XVT, a commercial interface-building package. In addition, CAS-2 will allow the KB to be run operationally in character-interface mode allowing access via telephone modem and via wide-area network. 5) A mode will be created which allows a CAS-2-based clinical advisor to be invoked in client-server mode, allowing any relevant clinical data already online to be passed automatically to the program. 6) Testing will include alpha- testing in collaboration with the Yale Center for Medical Informatics, and later beta-testing at other institutions.